DCMU problems

In article <199509150403.AA09060 at sequoia.itd.uts.EDU.AU>,
P.Ralph at uts.edu.au wrote:
>Dear Netters,
>>I've been trying for several months to run a series of DCMU treated
stress
>trials with the seagrass Halophila ovalis. Unfortunately, everything I
do
>causes a permanent and significant decline in the Fv/Fm ratio after
DCMU
>treatment before being exposed to the stress.
>>I've tried vacuum infiltration, treatment in the dark, treatment in the
>light and ranges of DCMU from 100 M to 1 M. Treatment times range from
15
>min down to 30 sec.
Perhaps you could give a bit more detail.
1. "100 M DCMU" is surely a misprint. Do you mean millimolar?
2. How are you measuring Fv and Fm. Are you doing the proper controls?
3. Quite possibly infiltration with 1% Tween has some effect. Do you
have a suitable control?
4. When you mention "exposure", do you mean exposure to just DCMU,
light...?
Jonathan B. Marder '
Department of Agricultural Botany | Internet: MARDER at agri.huji.ac.il
The Hebrew University of Jerusalem | /\/
Faculty of Agriculture |/ \ Phone: (08 or +9728) 481918
P.O.Box 12, Rehovot 76100, ISRAEL / Fax: (08 or +9728) 467763